AirDrop, which allows quick file transfer between Apple devices, was used by protesters at a July 7 rally in Hong Kong to tell shoppers visiting from China about their opposition to proposed changes to Hong Kong extradition law. Photo: Bloomberg

AirDrop, which allows quick file transfer between Apple devices, was used by protesters at a July 7 rally in Hong Kong to tell shoppers visiting from China about their opposition to proposed changes to Hong Kong extradition law. Photo: Bloomberg